Strip MySQL and MariaDB #ifdef versionsing
TokuDB code is littered with #ifdef for specific MySQL and MariaDB version functionality since they (Tokutek) preferred to maintain a single version branch rather than the Percona style workflow where we maintain a branch per major series.
Task is to carefully investigate each and remove anything not for the current version series/branch, this includes all MariaDB specific magic.
They should be merging 5.5 from the old tokutek repos as they will remain compatible with 5.5 and will likely never, ever change since we no longer support any of the tokutek builds (for bug fixes and features). Merging from PS 5.6 to Maria 5.5 isn't a good idea, ever.
BTW, MariaDB is merging from us to 5.5 too
Actually, I can see reason to leave them as is in PS 5.6 and remove from 5.7 onwards, but it does possibly create ongoing merge issues for us (me). These were supposed to have been all removed a year ago when we first imported the tokudb plugin into the PS codebase, but it never got done.
Why can't they take over ownership of them in their merges? They serve no purpose whatsoever in the PS codebase and they have already had to extend them themselves, it would be much easier to eliminate them entirely and let Maria maintain their own set of downstream patches instead of a random mix between the codebases.
MariaDB is merging from 5.6. I'd leave their ifdefs there.